import { Injectable } from '@angular/core';import { Http, Response } from '@angular/http';import { Observable } from 'rxjs/Observable';import 'rxjs/add/observable/from';import 'rxjs/add/operator/map';import { AdminUserInfo } from "./interfaces";@Injectable()export class AdminLoginService {    login(username:string, password:string, remember:boolean): AdminUserInfo {        if (username == "justin" && password == "123456") {            return new AdminUserInfo();        }        return null;    }}